Digital Photography Hacks

Analyze Metadata to Improve Your Shots

In the days of film cameras, I seldom recorded exposure settings that would have helped me better analyze my pictures. Now, digital cameras handle all that work for me, and I can use that information to figure out what went right or what went wrong.

Every time you click the shutter, your digital camera records valuable picture data that describes the image you just captured. Data such as time, shutter speed, aperture, focal length, and ISO are written to the file header in the Exchangeable Image File (EXIF) format. This information becomes part of the total image file and can be displayed with applications such as Photoshop.

In essence, each picture file contains a complete photographic history of the decisive moment, which can be analyzed to help you understand why the image was successful or give you clues as to what went wrong. In this hack, I’ll show you how to retrieve this data and use it to hone your photography skills.

What Is EXIF?

The EXIF format is an international specification, first established in 1995, that enables digital cameras (and other imaging devices) to write data to the file header of the image. EXIF files use the JPEG DCT format specified in ISO/IEC 10918-1. The picture portion of the file can be read by any application supporting JPEG, including web browsers and image editors. The metadata can be accessed by applications designed to extract that information out of the header and display it. The most common imaging applications ...